In a fuel injection valve of the above type, particularly one which is used for a spark ignition type internal-combustion engine, the diameter of the fuel discharge port is usually small (for example, less than 1 mm). It is therefore difficult to bore a hole serving as a fuel discharge port in the blank of the valve seat-forming member using a hole-forming member such as a drill, and then surface-finish the hole. In such case, an edge flashing remains and exerts a significant influence upon the fuel flow rate, depending upon the size of the edge flashing and the amount of peeling of the edge flashing due to the flow of the fuel. Moreover, high-level fuel injection control is required for a fuel injection valve of this type, and hence, it is desirable to surface-finish the fuel discharge port to remove such edge flashing and make the surface smooth in order to produce a high performance fuel injection valve.